The Value of Low-Maintenance Insulation in Distribution Hardware
Maintenance in electrical distribution is the subject of many studies that reveal higher maintenance costs than the purchase prices in life of the equipment. There is no better illustration of this than in insulation systems, or the line of defense between live and ground. The conventional insulation needs frequent maintenance, cleaning and in most cases change, thus using budgets and labor, which many utilities and industrial facilities can ill afford. This is changed with low-maintenance insulation systems that are constructed on high-technology material and accuracy in production. They provide reduced or eliminated routine maintenance, which offers low total cost of ownership, high reliability, and safety. Fully equipped with our line of dry-type, VPI and oil-immersed transformers, Jiangsu Ryan Electric delivers the benefits of low-maintenance insulation to the distribution hardware in the global market..
Understanding Insulation Degradation and Maintenance Drivers
To fully understand the worthiness of low-maintenance insulation, it is important to find out the reasons of conventional insulation failure in the first place. Conventional insulation systems; paper/oil mixtures used in liquid-filled transformer systems, or conventional epoxy used in dry-type systems, all deteriorate by a variety of mechanisms: thermal aging due to normal operation, absorption of moisture due to reduced dielectric strength, surface contamination leading to tracking and flashover, mechanical forces due to thermal cycling.
All these degradation mechanisms are motivating to maintenances. Oil-filled units require sampling and testing of oil periodically, with or without filtration or replacement. Traditional dry-type transformers must be washed down on a regular basis to eliminate conductive dust which can cause surface tracking. This maintenance is increased in adverse conditions such as coastal areas where salt sprays, industrial locations where there is chemical contamination, or dusty areas. The sophisticated insulation systems of Ryan Electric are designed to withstand such processes of degradation initially, eliminating or reducing the number of interventions expected during several decades of operation.
Cast Resin Technology: The Ultimate Low-Maintenance Solution
Cast resin dry-type transformers are the gold standard in low-maintenance insulation in applications where access to maintenance is hard or where the environmental conditions are especially problematic. Placing the windings in a solid dielectric material, in vacuum, unlike traditional dry-types, which utilize air as a component of the insulation system, the cast resin transformers of Ryan Electric encapsulate the windings with a solid dielectric material.
Several maintenance-saving advantages are obtained by this encapsulation. It is also coated with a sealed surface to avoid moisture absorption even on the area of 100 percent humidity, without the periodic drying or space heaters. The no-porous surface makes the furniture dust-and contamination-free, which saves cleaning by a big margin. The fire resistance property and self extinguishing nature of the material used remove the issue of maintenance of fire protection systems. Most notably, and perhaps the most important, cast resin insulation is practically immune to thermal cycling, i.e. expansion and contracting that slowly compromises the usual taped or wrapped type of insulation. In the case of data centers, commercial buildings and industrial facilities where an operational hiatus during maintenance is not an option, this reliability is directly translated to continued service.
VPI Processing: Extending Life in Harsh Environments
The Vacuum Pressure Impregnated (VPI) transformers of Ryan Electric are exceptional in terms of value to those who need the strength of liquid-immersed construction but the increased life of insulation. VPI process, which is the impregnation of windings with polyester or epoxy resin under the vacuum and pressure, removes the microscopic air pores that act as initiation sites of partial discharge and insulation breakdown.
The outcome is that a system of insulation is created which retains its dielectric properties even under the impact of thermal stress, mechanical vibration, and environmental contamination. In the case of distribution hardware in industry where Chemical vapors, conductive dust and high temperatures are routine, this translates into long periods between maintenance cycles. Windings that are treated with VPI are resistant to the ingress of moisture which would require oil reclamation in the traditional units. They preserve their mechanical integrity through repeated short-circuit stresses which are capable of loosening conventional constructions. And since the impregnation procedure completes the bonding of the winding structure, the insulation abrasion of vibration, a typical failure mode of old transformers, is eliminated virtually. This has been substantiated by field experience on our installations in more than 50 countries that Ryan Electric VPI transformers will generally have a longer life than conventional designs and will not need any major maintenance intervention.
Total Cost of Ownership and Sustainability Benefits
Low-maintenance insulation is more than just a cost in terms of labor and material. The maintenance saving due to high-quality insulation is frequently higher than the original price difference when the utilities and industrial facilities consider the purchase of transformers based on total cost of ownership (TCO).
Take an example of a distribution transformer that is placed in a distant place. Every service time needs movement, workforce, in many cases, special testing apparatus, and even outage organization. These costs may be multiplied, over a life span of 30 years service. Low-maintenance insulation systems offered by Ryan Electric cut or avoid most of these visits providing documented TCO benefits. In the case of oil-immersible units, our processing and design of insulation reduce the formation of the sludge and degradation of paper to extend the lifetime of the oil, and the processing and design of the insulation prevents or minimizes the reclamation. In the case of dry-type units in critical operations, the value of the removal of maintenance-related outages which incur some cost per hour in the form of lost production or lost service is immense to the equipment investment.
In addition to direct economics, less maintenance provides benefits of sustainability. Less visits to sites lead to reduced transportation emissions. Long oil life will imply a decreased disposal of waste oil. Prolonged life of the transformers implies delayed consumption of raw materials to replace units. To clients who are dedicated to environmental stewardship such as developers of renewable energy and operators of green buildings, Ryan Electric low-maintenance insulation systems will complement bigger sustainability plans and provide the dependability that the world projects require. Our distribution hardware is certified to IEEE, UL, CE and other international standards and tested in our CNAS-accredited test laboratories. The value of our distribution hardware is available and increases with every year of maintenance-free service.
